1. Field of the Invention
The present invention relates to a system and method for sending information between nodes. More specifically, the present invention relates to a system and method for sending electronic information between computers and/or networks over a secure pipeline in a manner that limits access between the computers and/or networks.
2. Discussion of Background Information
As is known to those of skill in the art, the movement of a data within a system governed by a particular protocol will attach or otherwise associate the data with a transport protocol header (TPH). Such a TPH will be consistent with the controlling protocol and contain at least sufficient information to forward the data from its source to its destination. Depending on the particular protocol, the TPH may include multiple headers; by way of non-limiting example, for the TCP/IP suite protocol, the TPH would include both IP and TCP headers. Manipulation of a TPH is a way in which crackers attempt to gain unauthorized access to a restricted computer or computer network.
The most common type of network security is a firewall, which prevents (or perhaps more correctly, limits) unauthorized access to or from a private network. The firewall may have several security measures, such as packet filtering, an application gateway, circuit-level gateway, a proxy server, etc. The firewall may include hardware, software, or a combination thereof. Notwithstanding the strength (or “height”) of a firewall, it is known that they are not impregnable. Several recent incidents of computer crackers breaking into high security public and private computer databases demonstrate that even the strongest of firewalls can be bypassed.
A weakness of the firewall approach is that both sides of the firewall tend to operate according to the same communication and transport protocols. For example, both the system protected by the firewall and an external system may operate using the TCP/IP protocol. To the extent that a cracker is able to breach or otherwise defeat the firewall, then manipulation of the TCP/IP TPH can be used to gain unauthorized access to the computer network.
In view of these potential vulnerabilities, many private and public agencies place sensitive electronic data on computers or computer networks that are not physically accessible to the outside world. Such a physical “air gap” between the sensitive data and the outside world completely prevents computer attack or invasion. Unfortunately, authorized data transfers from the computer or computer networks to outside computers are limited to manual transfer on a portable storage medium (e.g., floppy disc or CD).